How can I prevent black spot on my roses?
Posted by Dobies Staff on 24 June 2013 11:35 am
Rose black spot is a common fungal disease of cultivated and wild roses.  It thrives under warm, moist conditions and is more of a problem in wet summers. 

Purple black spots or blotches appear on the leaves which turn yellow and fall prematurely.  The fungal spores can overwinter on fallen leaves, stem lesions and on bud scales so collect any fallen leaves and in spring prune out any shoots which have lesions that could harbour spores. 

Immediately after pruning and before the leaves start to break, spray with one of the recommended fungicides such as  Fungus Clear or Systhane Fungus Fighter. A number of applications may be required during the growing season, following the manufacturer's recommendations.  Some products such as Rose Clear also contain an insecticide for the control of aphids.
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